1. Field of the Invention
The present invention relates to a jig that is to be used in press insertion in which, in the case where pipe members made of resin for transporting a liquid having high purity or ultrapure water to be handled in a production process in production of semiconductor devices, production of medical equipment and medicines, food processing, chemical industry, or the like are connected to each other by means of a pipe joint, a sleeve-like inner ring is pressingly inserted into an inner periphery of one end portion of each of the pipe members in order to enhance the sealing property between the one end portion of the pipe member and the pipe joint, and prevent the pipe member from slipping off.
2. Description of the Prior Art
Conventionally, as an example of a pipe joint made of resin of this kind a configuration shown in FIG. 14 is known (for example, Japanese Utility Model Publication No. 7-20471). The pipe joint made of resin shown in FIG. 14 comprises a joint body 50, a sleeve-like inner ring 23, and a union nut (pressing ring) 51 which are made of resin having excellent chemical and heat resistances, such as fluororesin. In the joint body 50, a receiving port 52 is formed in one end in the axial direction, and a primary sealing portion 53 is formed in an inner area of the receiving port 52 so as to intersect with the axis C of the joint body 50. A secondary sealing portion 54 is formed in an entrance area of the receiving port 52 so as to intersect with the axis C, and an external thread portion 55 is formed on the outer periphery of the receiving port 52. In the inner ring 23, a fitting portion 56 having an outer diameter that allows the portion to be fitted into the receiving port 52 of the joint body 50 is formed in an inner end portion in the axial direction, and a bulge portion 57 having a mountain-like section shape is formed in an outer end side in the axial direction. The inner ring 23 is pressingly inserted into one end portion of a pipe member 14 made of resin under a state where the fitting portion 56 projects outwardly, whereby the diameter of the one end portion of the pipe member 14 is increased. An inner end sealing portion 58 which abuts against the primary sealing portion 53 of the joint body 50 is formed in an end portion of the fitting portion 56, and an outer peripheral sealing face 59 which abuts against the secondary sealing portion 54 of the receiving port 52 is formed in a place corresponding to the bulge portion 57. In the union nut 51, an internal thread portion 60 which is to be screwed to the external thread portion 55 of the joint body 50 is formed.
The pipe member 14 is connected to the configured pipe joint made of resin in the following manner. Under a state where the one end portion of the pipe member 14 into which the inner ring 23 is pressingly inserted is inserted into the receiving port 52 of the joint body 50, the internal thread portion 60 of the union nut 51 which is previously loosely fitted onto the outer periphery of the pipe member 14 is screw-fastened to the external thread portion 55 of the joint body 50. This fastening causes the inner ring 23 to be pressed in the axial direction, so that the inner end sealing portion 58 and the outer peripheral sealing face 59 of the inner ring 23 abut against the primary and secondary sealing portions 53 and 54 of the receiving port 52 of the joint body 50, respectively, thereby exerting a sealing function (sealing force).
A jig for pressingly inserting the inner ring 23 into one end portion of the pipe member 14 is disclosed in, for example, Japanese Utility Model Publication No. 57-33983 and Japanese Patent Application Laying-Open No. 11-156750.
In the inner ring press-insertion jig disclosed in Japanese Utility Model Publication No. 57-33983, as shown in FIG. 15, an outer ring 63 is set on a pipe member holding portion 62 disposed in the front end side of a jig table 61, one end portion of the pipe member 14 is passed through the outer ring 63 and horizontally held, and a screw rod 65 is screwed with an external thread portion 64 disposed in the rear end side of the jig table 61 so as to be advanceable and retractable. A pressing piece 66 is formed integrally with the tip end of the screw rod 65. The pressing member 66 is fitted into a hole of an inner ring 67. When the screw rod 65 is rotated by a handle 68 to be advanced in the direction of the arrow A, the inner ring 67 is pressingly inserted and fixed into the inner periphery of one end portion of the pipe member 14, and the outer ring 63 is pressingly inserted and fixed onto the outer periphery of the member.
FIG. 16 is a side view of the inner ring press-insertion jig disclosed in Japanese Patent Application Laying-Open No. 11-156750, and FIG. 17 is a section view showing a state where press insertion of an inner ring is ended. Referring to FIGS. 16 and 17, an outer ring 72 is set on a pipe member holding portion 71 disposed in the front end side of a jig body 70, one end portion of the pipe member 14 made of resin is passed through the outer ring 72 and horizontally held, and a screw rod 77 is screwed with an internal thread portion 73 disposed in the rear end side of the jig body 70 so as to be advanceable and retractable. A ball joint 78 is disposed in a tip end portion of the screw rod 77. A pin holding member 79 is attached to the ball joint 78. The pin holding member 79 holds a pressing pin 80. The pressing pin 80 is inserted into an inner ring 81. When the screw rod 77 is rotated by a handle 82 to be advanced in the direction of the arrow A, the inner ring 81 is pressingly inserted and fixed into the inner periphery of one end portion of the pipe member 14 made of resin, and the outer ring 72 is pressingly inserted and fixed onto the outer periphery of the member.
In the inner ring press-insertion jig shown in FIG. 15, when the pressing piece 66 at the tip end of the screw rod 65 is firmly fitted into the hole of the inner ring 67, the inner ring 67 corotates with the screw rod 65 during the press insertion of the inner ring 67. Consequently, there arises a disadvantageous situation in which torsional deformation is applied to the pipe member 14. By contrast, in the inner ring press-insertion jig shown in FIG. 16, the pin holding member 79 and the pressing pin 80 can be relatively rotated, and hence torsional deformation is not applied to the pipe member 14 during the press insertion of the inner ring 81.
As the inner rings 67 and 81, rings of various sizes having different diameters are required so as to comply with the bore diameter of the counter pipe member 14.
In the inner ring press-insertion jig shown in FIG. 15, the pressing piece 66 which holds the inner ring 67 is formed integrally with the tip end of the screw rod 65, and hence cannot be detached from the screw rod. In the inner ring press-insert ion jig shown in FIGS. 16 and 17, similarly, the pressing pin 80 which holds the inner ring 81 cannot be detached from the tip end portion of the screw rod 77. In both the inner ring press-insertion jigs, for each of different bore diameters of the counter pipe member 14, therefore, it is necessary to prepare inner ring pressinsertion jigs of several kinds comprising the inner ring 67 or 81 of a size corresponding to the bore diameter of the pipe member.
The present invention is aimed at solving the noted problems. It is an object of the present invention to provide an inner ring press-insertion jig which can pressingly insert an inner ring into one end portion of a pipe member made of resin without applying torsional deformation to the pipe member, and which can singly cope with inner rings of several sizes. It is another object of the invention to provide an inner ring press-insertion jig in which operations of attaching and detaching a ring holder for holding an inner ring can be simplified. It is a further object of the invention to provide an inner ring press-insertion jig which can suppress generation of abrasion powder that should be prevented as far as possible from entering a pipe member made of resin in view of prevention of contamination.
The inner ring press-insertion jig for a pipe member made of resin of the invention will be described with reference to the accompanying drawings. The reference numerals in the figures are used in this paragraph in order to facilitate the understanding of the invention, and the use of the reference numerals is not intended to restrict the contents of the invention to the illustrated embodiments.
The inner ring press-insertion jig for a pipe member of the invention is an inner ring press-insertion jig for inserting a sleeve-like inner ring into one end portion of a pipe member. A pipe member holding portion (2) which horizontally fixedly holds one end portion of a pipe member (14) is placed in a front end side in a longitudinal direction of a jig body (1), and a press insertion rod supporting portion (3) is placed in a rear end side to be opposed to the pipe member holding portion. A press insertion rod (19) is passed through and supported by the press insertion rod supporting portion (3) in an advanceable and retractable manner. A ring holder (20) which has at a front end a ring holding shaft portion (20a) that is to extractably hold an inner ring (23) is detachably coupled to a front end of the press insertion rod (19) to be idly rotatable about an axis.
According to the configured inner ring press-insertion jig, when the press insertion rod is advanced after one end portion of the pipe member is fixedly held by the pipe member holding portion and the inner ring is held by the ring holder, the inner ring can be pressingly inserted into the one end portion of the pipe member.
The ring holder is coupled to the front end of the press insertion rod so as to be idly rotatable about the axis. After the insertion, therefore, the ring holder can be extracted from the inner ring in the pipe member without applying torsional deformation to the pipe member. Since the ring holder is detachably coupled to the front end of the press insertion rod to enable replacement of the ring holder, the single jig can be commonly used for press insertion of inner rings of various diameters.
The configuration for coupling detachably and idly rotatably the ring holder (20) to the front end of the press insertion rod (19) may be specifically structured in the following manner. An internal thread hole portion (29) is disposed in a center portion of a front end face of the press insertion rod (19), a coupling shaft portion (20b) protrudes rearwardly from a center portion of a rear end face of the ring holder (20), a holder block (26) is passed idly rotatably and lockedly through the coupling shaft portion (20b), the holder block having: a cylindrical portion (24) in which an external thread portion (24a) is formed on an outer periphery; and a flange (25) which is formed integrally with a front end of the cylindrical portion, and the external thread portion (24a) of the cylindrical portion (24) is screwingly coupled to the internal thread hole portion (29).
According to the inner ring press-insertion jig, the ring holder can be easily attached to or detached from the press insertion rod by a simple operation of fastening or loosening the holder block to or from the internal thread hole portion of the press insertion rod by means of the screwing of female and male thread portions. Since the coupling shaft portion of the ring holder is passed through the long cylindrical portion which elongates in the axial direction of the holder block, the ring holder is held stably and idly rotatably in a cantilevered manner without causing runout.
In this case, a washer (27) made of low-friction resin may be interposed between the rear end face of the ring holder (20) and the flange (25) of the holder block (26). According to this configuration, the ring holder can be smoothly idly rotated, and generation of abrasion powder that is prevented as far as possible from entering a pipe member made of resin in view of prevention of contamination is prevented from occurring between the rear end face of the ring holder and the flange of the holder block.
At least one of the ring holder (20) and the holder block (26) may be formed by a low-friction resin material. According to this configuration, the ring holder can be smoothly idly rotated, and generation of abrasion powder is prevented from occurring between the outer peripheral face of the coupling shaft portion of the ring holder and the inner peripheral face of the cylindrical portion of the holder block.